Process of making a cleated floor mat

ABSTRACT

The present invention relates to specific methods of producing cleated rubber-backed floor mats (such as dust control or rubber mats) through the utilization of the combination of a perforated coated woven fabric article and a cushioned platen liner between the article and the metal platen of an in-line dust control mat manufacturing machine. Such a procedure permits a more efficient manner of producing cleated anti-creep dust control mats than previously followed. In particular, the fabric article is in the form of a conveyor belt and is preferably constructed from Teflon®-coated woven fiberglass which will not adhere to the tacky rubber component of the target mat and can withstand the extremely high vulcanization temperatures and pressures required during the production of a dust control mat. The cushioned platen liner, which is preferably comprised of or coated with silicon, is utilized as a separator between the metal platen of the manufacturing machine, as well as cushion for the molten rubber as it is pressed through the conveyor belt perforations during vulcanization. Such a cushioned liner material substantially eliminates any problems due to the force of the metal platen against the molten rubber as it passes through the article perforations. The produced mat as well as the woven fabric article/cushioned platen liner combination are also encompassed within this invention.

FIELD OF THE INVENTION

The present invention relates to specific methods of producing cleatedrubber-backed floor mats (such as dust control or rubber mats) throughthe utilization of the combination of a perforated coated woven fabricarticle and a cushioned platen liner between the article and the metalplaten of an in-line dust control mat manufacturing machine. Such aprocedure permits a more efficient manner of producing cleatedanti-creep dust control mats than previously followed. In particular,the fabric article is in the form of a conveyor belt and is preferablyconstructed from Teflon®-coated woven fiberglass which will not adhereto the tacky rubber component of the target mat and can withstand theextremely high vulcanization temperatures and pressures required duringthe production of a dust control mat. The cushioned platen liner, whichis preferably comprised of or coated with silicon, is utilized as aseparator between the metal platen of the manufacturing machine, as wellas cushion for the molten rubber as it is pressed through the conveyorbelt perforations during vulcanization. Such a cushioned liner materialsubstantially eliminates any problems due to the force of the metalplaten against the molten rubber as it passes through the articleperforations. The produced mat as well as the woven fabricarticle/cushioned platen liner combination are also encompassed withinthis invention.

BACKGROUND OF THE PRIOR ART

All U.S. patent cited herein are hereby fully incorporated by reference.

Floor mats have long been utilized to facilitate the cleaning of thebottoms of people's shoes, particularly in areas of high pedestriantraffic such as doorways. Moisture, dirt, and debris from out of doorseasily adhere to such footwear, particularly in inclement weather andparticularly in areas of grass or mud or the like. Such unwanted andpotentially floor staining or dirtying articles need to be removed froma person's footwear prior to entry indoors. As will be appreciated, suchoutdoor mats by their nature must undergo frequent repeated washings anddryings so as to remove the dirt and debris deposited thereon duringuse. These mats are generally rented from service entities whichretrieve the soiled mats from the user and provide clean replacementmats on a frequent basis. The soiled mats are thereafter cleaned anddried in an industrial laundering process (such as within rotary washingand drying machines, for example) and then sent to another user inreplacement of newly soiled mats. Furthermore, it is generally necessaryfrom a health standpoint to produce floor coverings on which persons maystand for appreciable amounts of time which will provide comfort to suchpersons to substantially lower the potential for fatigue of such personsby reducing the stress on feet and lei joints through cushioning.

Typical carpeted dust control mats comprise solid and/or foam rubberbacking sheets which must be cleated in some manner to prevent slippageof the mat from its designated area. Such cleats are formed during avulcanization step and have required a time-consuming procedure ofplacing the green (unvulcanized) rubber sheet on a molded, perforatedsilicone pad which is itself placed by hand on the conveyor belt of adust control manufacturing apparatus. The finished mat is then removedafter vulcanization from the non-stick silicon pad. The resultant matproduct possesses cleats formed through the melting and forcing of partof the rubber backing through the pad perforations during vulcanization.Such cleats provide anti-slip or anti-creep characteristics to thefinished mat when placed upon a surface to be protected. Various types,shapes, and arrangements of cleats have been utilized in the past forsuch anti-creep benefits with dust control mats. Examples include U.S.Pat. Nos. 4,741,065 to Parkins, 5,170,526 to Murray, and 5,227,214 toKerr et al.

As noted above, previous methods of providing such cleat features torubber-backed mats are generally produced through the utilization of aperforated silicon pad which is placed by hand on a conveyor belt on inin-line vulcanization apparatus. A rubber article is then placed on topof silicon pad, and optionally a fabric pile (such as a carpet) is thenplaced, again by hand, on top the rubber article. The conveyor belt thentransports the entire composite to a vulcanization chamber wherein it ispressed at a pressure of from about 25 to about 40 psi at a temperatureof from about 300 to about 400° F. for anywhere between about 30 secondsand 20 minutes. After vulcanization, the conveyor belt transports thefinished composite (floor mat plus silicon pad) out of the chamber. Thefloor mat is then removed from the pad and allowed to cool and the padis moved, by hand, back to a location on the conveyor belt, prior to thechamber, in order for another rubber article to be placed thereon. Sucha procedure is labor-intensive and inefficient. However, until now,there have been no disclosures of proper methods to reduce the time andlabor required to effectively and efficiently produce rubber-backedcleated floor mats. There have been developments in conveyor belts,particularly those covered with Teflon® coatings, for utilization inother rubber molding processes. However, there has been no discussion orsuggestion regarding the problems associated with cleat-formingperforated conveyor belts in the past. In light of the above, it will beappreciated that there is a need for a process and apparatus toefficiently produce cleats within the rubber backing of an anti-creepfloor mat. The present invention thus represents a useful advancementover prior practice.

OBJECT OF THE INVENTION

In view of the foregoing, it is a general object of the presentinvention to provide an in-line method for the production of cleats in arubber or rubber-backed floor mat. Furthermore, it is an object of thisinvention to provide a novel conveyor belt system for an in-line floormat manufacturing apparatus. Additionally, an object of this inventionis to provide a cleated anti-creep floor mat which is more easily andefficiently produced than standard cleated floor mats. Still anotherobject of this invention is to provide an anti-creep floor mat whichexhibits not only cleats to provide anti-slip characteristics, but alsointermittent patterned areas within the rubber on the underside of therubber floor mat component which mirrors the woven structure of theperforated fabric article.

Accordingly, this invention encompasses a method of producing a cleatedanti-creep floor mat comprising a rubber mat component with a matproducing apparatus comprising the steps of:

(a) providing a perforated woven fabric article, which is coated orcomprised of a material which will not adhere to said rubber matcomponent after a vulcanization step, wherein said perforated wovenfabric article is optionally separated from the metal platen of saidapparatus by a cushioned platen liner;

(b) placing said rubber mat component on top of said perforated wovenfabric article of step “a” and optionally placing thereon a fabric pile;

(c) transporting the rubber mat component/perforated woven fabricarticle composite to a vulcanization chamber; and

(d) vulcanizing said rubber mat component as it remains on top of theperforated woven fabric article, thereby forming cleats through theperforations of said perforated woven fabric article;

wherein said woven fabric article and said optional platen liner arecomprised of or coated with materials which can withstand thetemperatures and pressures associated with vulcanization. Also, thisinvention concerns a floor mat manufacturing apparatus having a metalplaten wherein said apparatus further comprises a perforated conveyorbelt positioned on top of a cushioned platen liner which is positionedon top of said metal platen. Additionally, this invention encompassesfloor mat article comprising at least a rubber sheet component whereinsaid rubber comprises a plurality of cleats formed integrally on thesurface and at least a portion of the surface of said rubber sheet alsocomprises a weave pattern of molded rubber.

The term “perforated” or “perforations” is intended to encompass anyconfiguration of holes within the woven fabric article structure throughwhich molten rubber may be forced during vulcanization. Thus, any shapehole, any orientation of holes, and any depth of such holes isencompassed within such a term. Preferably, the holes (perforations) arecircular in shape ultimately to produce cylindrically shaped cleats inthe target mat article. Also, the diameter of such perforations arepreferably from about {fraction (1/64)} inch to about ¼ inch; morepreferably from about {fraction (1/32)} inch to about ⅛ inch; and mostpreferably from about {fraction (3/32)} to about {fraction (1/16)} inch.

Preferably, the perforated woven fabric article of the instant inventionexhibits a modulus of from about 70 to about 100 on the Shore A HardnessScale and is present in the form of a conveyor belt which therebypermits an in-line mat production procedure. In such a form, the platenliner must be utilized under the conveyor belt in order to reduceoff-quality cleat production, as discussed below. However, if desired,the woven fabric article may also be a separate article which is cutfrom a web of fabric which can be placed by hand on a cushioned platenliner and/or on a standard conveyor belt within a mat a manufacturingapparatus. After vulcanization, the finished mat can easily be removedfrom the fabric article and the fabric article can then be transportedto a pre-vulcanization location for placement of another rubber matcomponent thereon. The preferred conveyor belt of the instant inventionmust be constructed of material which not only can withstand continuousand/or repeated movement around a rotating drum and through a standardin-line floor mat manufacturing apparatus; such materials (including thecut-out forms of such woven fabric articles) must also be able towithstand the high temperatures and pressures associated with rubbervulcanization. The core material of such a belt or cut-out is thuspreferably fiberglass although other materials, such as polyaramids,silicon, and the like, may also be utilized. The belt or cut-out shouldalso be coated with a covering which can also withstand vulcanizationtemperatures and pressures and not appreciably adhere to molten rubber.Silicon may be utilized for this purpose as well; however, the preferredcoating is polytetrafluoroethylene, also known as Teflon®, availablefrom DuPont. The preferred conveyor belt (or cut-out fabric) is firstproduced by taking a woven (or non-woven) fiberglass fabric and coatingit with a certain number of Teflon® layers. Perforations are then cutinto the coated fabric to conform with the desired shape and orientationof ultimately formed cleats on the target floor mat article. Then, thecut fabric is coated with a few more layers of Teflon® in order toinsure the potentially frayed fibers of the cut fiberglass will notinterfere with the eventual removal of the target floor mat article fromthe belt surface. If such frayed fiber ends were not coated themselves,they could adhere to the mat and produce aesthetically displeasingresults. The coated fabric, and thus the belt itself, may have athickness of from about {fraction (1/64)} inch to about ¼ inch,depending on the desired size of the ultimately formed cleats. Thethickness of the fabric (belt) dictates the length of the projectedcleats from the rubber surface of the mat article since, upon meltingduring vulcanization, the rubber will become forced through theperforations of the belt a distance roughly the same as the beltthickness. Preferably, the cleat lengths are from about {fraction(1/64)} to ¼ inch, more preferably from about {fraction (1/32)} inch toabout ⅛ inch; most preferably about {fraction (3/32)} inch.

The woven structure of such a fabric article is of vital importance toprovide an extra anti-slip weave pattern feature to the finished floormat product. Since woven fabrics exhibit differing textures at theirsurfaces due to the interlacing and crossovers of the individual yarnswithin the woven structure, the mirror image of such a woven structurewill be transferred to the target rubber mat component duringvulcanization as long as the fabric article remains in place under therubber component during such a step. In the past, the production ofcleats has been performed, as noted above, with silicon pads, and thelike, which produced discrete cleats within the rubber mat component butgenerally did not include any anti-slip features between such producedcleat formations. Through the utilization of such a woven structure, theresultant fabric pattern can thus be transferred to the rubber surfacewhich provides a roughened surface between produced cleats for improvedanti-slip characteristics within the inventive floor mat.

Prior to incorporating the aforementioned preferred conveyor belt to afloor mat manufacturing apparatus (which generally comprises a metalplaten over which the conveyor belt would be placed directly), acushioned platen liner is placed over the metal platen. A platen linermay be placed beneath the cut-out woven fabric article as well; however,since the hand-placed fabric article would most likely be placed on aconveyor belt itself, or placed within a shelf-type vulcanizationchamber, some degree of cushioning would already be provided which couldrender the utilization of such a platen liner unnecessary.

In general, it has been discovered that the platen liner should bepresent to avoid the creation of “flared” cleats in the final matproduct. Such a problem is caused by both the lack of adhesion betweenthe molten rubber and the Teflon®-coated fabric surface as well as theforce of the metal platen on the molten rubber forced through the fabricperforations. Without a cushioning platen liner, when the vulcanizationchamber presses down on the mat article, the rubber, upon melting, isforced through the perforations into the metal platen. The force of thestationary metal platen then forces the rubber back toward the belt andrubber article; however, the molten rubber will seek the path of leastresistance rather than returning through the perforation it cameoriginally. Without the adhesion between the fabric and the rubber, therubber will easily move between the fabric and the platen. In such aninstance, upon exiting the vulcanization chamber, the mat article is noteasily removed from the belt (since the rubber forms “hooks” on theunderside of the belt). The resultant mat article thus exhibitsaesthetically displeasing pleasing cleat formations which themselvespossess suspect effectiveness as preventing slippage or creeping of themat when placed on a protected surface. Hence, it was discovered that inorder to provide such an efficient procedure of in-line cleat formingfor floor mat articles, a cushioned platen liner was required toseparate the fabric article (belt) from the metal platen and to providecushioning of the rubber to prevent re-forcing back toward the beltitself during vulcanization. However, such a platen liner may not berequired when a cut-out article is utilized to produce the desiredcleats, most notably when the conveyor belt itself (which may be coatedrubber, or other fabric, for example) within the mat manufacturingapparatus provides the necessary cushioning effect; but, other timesthere will be a need to utilize such a cushioned article to reduce theproduction of off-quality cleats.

When present, the platen liner preferably covers the entire area of themetal platen over which mat articles will be placed. Preferably, theplaten liner will possess a modulus of from about 40 to 70 on the ShoreA Hardness Scale in order to provide the necessary cushioning effectsfor proper cleat formation. Preferably, the modulus is about 50 on thesame scale. Furthermore, the platen liner must be able to withstand thehigh temperatures and pressures associated with rubber vulcanization.Thus, the liner must be constructed from material which possesses bothcharacteristics. The preferred material is a rubber coated with silicon(Available from Taconic, for example) which exhibits a Shore A Hardnessof about 50. However, the liner may also be constructed from otherheat-resistant materials which have been incorporated within flexiblefabrics, rubber, and the like, and/or alternatively coated with aheat-resistant material, such as Teflon®, silicon, and the like. Thethickness of such a liner is not of great importance, although, thethicker the better (for cushioning purposes). The utilization of toothick a liner will not seriously impact the effectiveness of theperforated conveyor belt in producing the desired cleats; however, assilicon liners are rather expensive, the thickness should be dictatedprimarily by cost versus available cushioning characteristics. As such,a thickness of from about {fraction (1/64)} inch to about ½ inch ispreferred; {fraction (1/64)} to about ⅛ inch more preferred; and{fraction (1/64)} inch to about {fraction (1/32)} inch most preferred.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an aerial cross-sectional view of the composite of platen,platen liner, conveyor belt, and floor mat constructed to produce theinventive floor mat.

While the invention will be described in connection with preferredembodiments and procedures, it is to be understood that the invention isin no way intended to be limited by such description. On the contrary,it is intended to cover all alternatives, modifications and equivalentsas may be included within the true spirit and scope of the invention asdefined by the claims appended hereto.

DETAILED DESCRIPTION OF THE DRAWING

Turning now to the drawing wherein like reference numerals designatelike components in the various views, in FIG. 1 there is shown inprofile the composite of different utilized components for production ofthe inventive floor mat article 10. In the illustrated and preferredpractice, a rubber mat backing sheet 12 is covered with, at leastpartially, and attached to (during vulcanization) a pile fabric 14 toform the desired floor mat 10. Cleats 24 are formed in certain locationson the underside of the rubber mat backing sheet 12 through placement ofthe sheet 12 (with or without the pile fabric 14 on top, preferablywith) over a woven fabric article, in this instance a conveyor belt 16,which is formed from woven fiberglass and coated with Teflon® and whichcomprises cut-out holes 25 in certain locations on the belt 16 whichcorrespond to the desired pattern of cleats 24 to be formed on thebacking sheet 12. The woven structure 27 of the conveyor belt 16 alsotransfers such a woven pattern 26 to the backing sheet 12 to provideincreased slip resistance supplemental to the cleats 24. In order topermit proper cleat formation on the backing sheet 12, a cushionedplaten liner 18 made from silicon rubber is present underneath theconveyor belt 16. All of these layers of articles are placed upon themetal platen 20 of a mat manufacturing apparatus (not illustrated). Thefloor mat 10 has already been transferred by the belt 16 through avulcanization chamber (not illustrated). Upon removal from the belt 16,the floor mat possesses the desired cleats 24 and woven patterns 26 foranti-creep benefits upon use.

While specific embodiments of the invention have been shown anddescribed, it will be understood, of course, that the invention is notlimited thereto, since modifications may be made and other embodimentsof the principles of this invention will occur to those skilled in theart to which this invention pertains. Therefore, it is contemplated bythe appended claims to cover any such modifications and otherembodiments as incorporate the features of this invention within thetrue spirit and scope of the following claims.

What we claim is:
 1. A method of producing a cleated anti-creep floormat with a mat producing apparatus comprising a rubber mat componentcomprising the steps of: (a) providing a perforated woven fabricarticle, which is coated or comprised of a material which will notadhere to said rubber mat component after a vulcanization step, whereinsaid perforated woven fabric article is optionally separated from themetal platen of said apparatus by a cushioned platen liner; (b) placingsaid rubber mat component on top of said perforated woven fabric articleof step “a” and optionally placing thereon a fabric pile; (c)transporting the rubber mat component/perforated woven fabric articlecomposite to a vulcanization chamber; and (d) vulcanizing said rubbermat component as it remains on top of the perforated woven fabricarticle, thereby forming cleats within said rubber mat component throughthe perforations of said perforated woven fabric article; wherein saidwoven fabric article and said optional platen liner are comprised of orcoated with materials which can withstand the temperatures and pressuresassociated with vulcanization.
 2. The method of claim 1 wherein saidconveyor belt is made of fiberglass and coated with a coating which canwithstand the high temperatures and pressures associated with rubbervulcanization and which will not adhere to said rubber mat componentafter a vulcanization step.
 3. The method of claim 2 wherein saidcoating is polytetrafluoroethylene.
 4. The method of claim 1 whereinsaid platen liner is either comprised of silicon or is coated withsilicon.